While it’s a bit hard to know exactly when a dealer is more likely to bust in blackjack, you can learn when a dealer is more likely to bust.
To begin with you must train you mind to except that there is no such thing as a dealer “bust card.” As much as we would like to see a certain card and think that the dealer will bust, it just isn’t true.
However there are some cards that the dealer is more likely to bust with: he has a 40% chance with a 4 and a 42% chance with a 5 or 6. But notice that’s still less than half the time.
So you can assume that you have a slightly better chance of winning than win the dealer is showing an Ace—the dealer will only bust 17% of the time then. Here’s the up card and busting breakdown:
But keep this in mind and then take a look at your basic strategy chart. Think of your hard hands. Why do you stand on a stiff hand when the dealer is showing a 2 through 6? This would be because the dealer’s chances of busting, while still less than half, have a greater chance of busting then.
This is also why you hit win the dealer has less of a chance of busting. It becomes your strategy to take a course of action that could give you a stronger hand. Take for instance that the dealer has a 10 showing and you have a 16. If you use the usual blackjack assumption that the hole card is a 20, then you know that your 16 will lose. So rather than go down without a fight, you can try hitting for a card that will give you at least a 20 or maybe even a 21.
These percentages of when a dealer is more likely to bust should further reinforce the need to follow basic strategy. When the basic strategy chart was made and its testing done, the chances of the dealer busting were taken into consideration. The best you can do in blackjack initially is to follow basic strategy.